The integration of trees into parking transforms the two-dimensional footprint of the car bays into a three-dimensional "eco-service", dramatically increasing community benefits per unit area. Tree crowns above our heads help to buffer urban temperature extremes, improve human well-being, intercept rainwater, enhance ecological diversity and ameliorate particulate pollution.
Beneath our feet are further opportunities to add value to the volume of space occupied by tree roots. Products such as the DeepRoot Silva Cell (www.deeproot.com) provide a rich rooting environment for the tree while supporting the surfacing above. Furthermore, this soil volume can store surges in rainwater, buffering its entry into the drainage system and reducing the flood risk.
Government policy has recognised these benefits in the Communities and Local Government consultation on climate change and the natural environment. Planning for a Natural and Healthy Environment (www.communities.gov.uk) emphasises the role of trees in creating attractive, sustainable communities.
This thrust is mirrored in the recent CABE announcement that Martin Gammie, an arboriculturist with South Oxfordshire District Council, has been awarded a scholarship to investigate how the USA, Canada and Sweden are incorporating trees into their urban areas.
The Government is developing a robust policy framework, backed up with solid support at the practical level. The challenge for uninformed planners, unimaginative architects and profit-obsessed mass retailers is to catch up and start delivering what we need - green car parks to spearhead our national climate adaption effort.
- Jeremy Barrell is managing director at Barrell Tree Consultancy.
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